JP2008139413A - Resonance sound generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a musical tone generator capable of reproducing resonance sound of half damper. <P>SOLUTION: A normal sound generation part 18 generates a normal sound signal in response to key touch and inputs it to an addition part 21. A resonance sound generation part 19 generates a resonance sound signal based on either one of a musical tone resonance sound waveform and an overtone resonance sound waveform selected in accordance with a pedal stepping-down volume PV, and inputs it to a multiplication part 22 as a gate. When the stepping-down volume PV is large, the gate is opened and the resonance sound can be generated. A switching part 20 selects the musical tone resonance sound waveform when the stepping-down volume PV is larger than a value RT, and selects the overtone resonance sound waveform with a resonance sound waveform selection judgement part 23 when the stepping-down volume is smaller than the value RT. When sound is muffled, a musical tone generation control part 25 varies an attenuation speed according to whether the stepping-down volume PV is larger than a threshold OT. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a resonance generator, and more particularly to a resonance generator suitable for simulating the effect of a half damper pedal in an acoustic piano.

  In an acoustic piano, the damper that holds the strings is removed from the strings with the damper pedal, and a performance technique is taken that resonates not only the strings actually played but all other strings. In an electronic musical instrument such as an electronic piano or an electronic organ, a function of simulating a string resonance sound by operating the damper pedal is required.

  For example, a normal piano sound that does not operate the damper pedal and a piano sound that includes the resonance sound when the damper pedal is operated are recorded, and each waveform data is stored, and the waveform is changed depending on whether or not the damper pedal is operated. A method of selecting and generating musical sounds has been done.

  In addition, the present inventors waveformd the string resonance waveform when the key was depressed after the damper pedal was turned on (musical sound resonance waveform) and the string resonance waveform when the damper pedal was turned on after the key was depressed (harmonic resonance waveform). There has been proposed a resonance generator that is stored in a memory and can control the reading of the tone resonance waveform and the harmonic resonance waveform according to the timing of key depression and damper pedal operation (Japanese Patent Application No. 2006-011470). issue).

  However, the performance method using the damper pedal is not limited to the two states of on and off, and there is also a performance method of changing the degree of attenuation by adjusting the depression amount between on and off. This is a so-called “half pedal” performance. However, the resonance sound generator proposed previously by the present inventors has room for improvement in terms of simulating the effect of the half pedal.

As an electronic musical instrument that simulates the effect of this half pedal, when the damper pedal is operated, the electronic key-off process is suspended and the volume attenuation rate can be changed according to the amount of depression of the damper pedal. There has been proposed an electronic musical instrument having a control means for controlling an attenuation rate of an envelope according to a determination result of whether or not a damper is in a state of suppressing string vibration (Japanese Patent Laid-Open No. 10-161658). Issue gazette).
JP-A-10-161658

  In the electronic musical instrument described in Patent Document 1, since the decay time of the normal sound is simply increased, the effect of the damper pedal that continues the sound after the key release when the damper pedal is fully depressed is obtained. Can be simulated. However, in the case of an acoustic piano, a small resonance sound peculiar to a half pedal is generated in a half pedal state in which the damper is slightly separated from the string. The conventional technique described in Patent Document 1 has a problem in that this resonance sound cannot be simulated.

  In view of the above problems, an object of the present invention is to provide a resonance generator that can simulate a small resonance peculiar to a half pedal.

  In order to solve the above problems and achieve the object, the present invention includes a normal sound generating means for generating a normal sound in response to a sound generation instruction, a first resonance sound of the normal sound in response to the sound generation instruction, and One of the first resonance sound and the second resonance sound depending on resonance sound generating means capable of selectively generating the second resonance sound and whether or not the operation amount of the damper operation element is equal to or greater than a resonance sound selection threshold. Resonance sound selection determining means for selecting one, level control means for controlling the level of the resonance generated by the resonance generating means in accordance with the operation of the damper operating element, and the normal operation in accordance with the operation of the damper operating element. An envelope control means for determining envelope control information for the sound generation means and the resonance sound generation means; and a musical sound mixing means for adding the normal sound and the resonance sound whose level is controlled by the level control means. There are first features.

  For example, the resonance generation means includes waveform data of the first resonance generated from the normal sound read from the waveform memory, and waveform data of the second resonance generated from the harmonic component of the normal sound, Based on the above, the sound source means generates the first resonance sound or the second resonance sound, respectively. The resonance sound selection determination threshold is set in advance corresponding to, for example, a timbre or pitch.

  According to the present invention, the level control means changes the resonance level from zero to a predetermined value at a first predetermined time when the damper operation element is turned on, and the damper operation element. And a means for changing the level of the resonance sound from the first scheduled value to zero at a second scheduled time different from the first scheduled time when the operation is turned off. A third feature is that the level control means is configured to change the level of the resonance sound from a predetermined value to zero corresponding to the operation amount of the damper operator. . The scheduled value of the level change of the resonance sound is set in advance corresponding to, for example, a tone color or a pitch.

  Further, the present invention is configured such that the envelope control means individually controls the decay time of the normal sound and the resonance sound during sound generation in response to the operation amount of the damper operation element when the sound generation stop instruction is input. This is the fourth feature.

  A fifth feature is that the first resonance sound or the second resonance sound is generated when the sound generation instruction is a sound generation instruction in a predetermined pitch or pitch range.

  Further, the present invention provides two resonance sound selection determination thresholds, and selects the first resonance sound when the operation amount of the damper operation element is equal to or higher than the resonance sound selection determination threshold value. In addition, the damping time of the first resonance sound is set to be slower when the operation amount of the damper operation element is higher or lower than the threshold value for determination of resonance sound selection and lower than the threshold value for determination of resonance sound selection. This is the sixth feature.

  In the present invention, a threshold value for gate opening determination is set below the threshold value for determining resonance selection, and when the operation amount of the damper operator is equal to or greater than the threshold value for gate opening determination, A seventh feature is that the first resonance sound and the second resonance sound selected by the sound selection determination means are allowed to be generated.

  In the present invention, the waveform data of the first resonance sound and the waveform data of the second resonance sound are input to the circuit group in which a plurality of resonance circuits corresponding to the harmonics of the tone that can be generated are connected in parallel. There is an eighth feature in that the waveform data is obtained in advance and stored in the waveform memory of the resonance generating means in advance.

  The resonance circuit has a digital filter, and its impulse response is a simulation of a harmonic vibration waveform by a one-degree-of-freedom viscous damping system model, and a filter coefficient used in the digital filter is one-degree-of-freedom. Given the mass, damping natural frequency, and damping rate as model parameters for determining the behavior of the viscous damping system model, obtain the viscosity and stiffness coefficients that are the coefficients of the model's equation of motion. Laplace transform is performed to obtain a transfer function expression of s expression, and the viscosity coefficient, rigidity coefficient and mass obtained are substituted into this, bilinear transformation is performed to obtain a filter coefficient of z expression, and the mass is an arbitrary value. The attenuation natural frequency is the frequency of the harmonic to be simulated, and the attenuation rate is obtained as an exponent when the attenuation of the harmonic is approximated by an exponential function. It is determined by Rukoto.

  According to the present invention having the first to eighth characteristics, when the sounding start instruction is input, that is, when the keyboard instrument is depressed, the first resonance is detected when the operation amount of the damper operator is equal to or greater than the resonance sound selection determination threshold. When a sound is selected and the operation amount of the damper operation element is less than the resonance sound selection determination threshold, the second resonance sound is selected. Therefore, different resonance sounds can be generated when the damper is operated with a full damper and when the damper is operated with a small damper. When the operation amount of the damper operation element is small, for example, a second resonance sound is generated as a second resonance sound, for example, a harmonic resonance sound that is a string resonance sound when the damper pedal is turned on after pressing the key on a keyboard instrument, In addition, it can be attenuated with normal sound at an appropriate speed to reproduce the half pedal effect of an acoustic piano.

  According to the present invention having the fourth feature, the decay time of the normal sound and the resonance sound being sounded can be individually controlled according to the amount of operation of the damper operator, so that long decay according to the full damper is achieved. The time can be set, and a delicate damped resonance sound with a relatively short decay time corresponding to the half damper can be generated.

  According to the present invention having the fifth feature, the first resonance sound or the second resonance sound is generated only in response to a sound generation instruction for a normal sound in a preset sound or range. For example, the first resonance sound or the second resonance sound can be generated in the high sound range, and only the first resonance sound can be generated in the low sound range. That is, it is possible to generate the harmonic resonance sound only in the high sound range where the level of the direct sound is large.

  According to the present invention having the sixth feature, even if the operation amount of the damper operation element falls within the range of the full pedal, only the first resonance sound is generated in the portion where the operation amount of the damper operation element is small. According to the pedal, when the sound is stopped, the decay time can be made slightly shorter than that at full damper.

  According to the present invention having the seventh feature, no resonance is generated when the amount of operation of the damper operator does not exceed the gate opening determination threshold value.

  According to the eighth feature, it is possible to easily obtain the resonance signal by inputting the tone signal to the resonance circuit. In particular, by appropriately setting the parameters of the one-degree-of-freedom viscous damping system model, it is possible to reproduce a desired vibration waveform and generate a desired resonance sound.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 2 is a block diagram showing a hardware configuration of an electronic piano including a resonance generator according to an embodiment of the present invention. In the figure, a CPU 1 controls each part shown in the figure via a system bus 2. The ROM 3 has a program memory 3a for storing programs used in the CPU 1 and a data memory 3b for storing various data including at least timbre data. The RAM 4 temporarily stores various data generated in the control by the CPU 1.

  Further, the electronic piano is provided with an operation panel (hereinafter simply referred to as “panel”) 5, a MIDI interface 6, and a damper operator, that is, a damper pedal (hereinafter simply referred to as “pedal”) 7. The panel 5 is constituted by switches for setting various states including a tone color switch 5a for selecting a tone color of a musical tone to be generated. Information set from the panel 5 is supplied to the CPU 1. The pedal sensor 7a detects the operation state of the pedal 7, that is, the amount of depression, as pedal information and supplies it to the CPU 1. The pedal sensor 7a is configured to include a variable resistor, and detects a change in voltage caused by the variable resistor as an amount of depression of the pedal 7.

  The keyboard 8 is composed of 88 keys, and each key is provided with a key switch 8a composed of a touch sensor. The key switch 8a detects the operation of the keyboard 8 by the performer, and generates a tone code corresponding to the key code KC (also referred to as key number) indicating the pitch of the pressed key, and key depression / release. Key information such as key-on KON / key-off KOFF for instructing the mute timing, key touch KT which is a key pressing speed or a key pressing strength is output. Information output from the key switch 8 a is supplied to the CPU 1 via the system bus 2.

  From the viewpoint that sound generation is started by pressing the key in the electronic piano shown in FIG. On the other hand, with respect to key release, if the pedal is operated at the time of key release, the sound generation is not stopped immediately by the key release, but in this specification, for convenience, the key release is regarded as a sound generation stop instruction and the sound generation stop instruction The time of input means the time of key release.

  The tone generator 9 is composed of a tone generator having channels that are time-division controlled to simultaneously generate a plurality of sounds, and accumulates and outputs the output signals of all the plurality of channels. In the musical sound generating unit 9, any channel is assigned by a key pressing operation, and a musical sound corresponding to the key pressing operation is generated in the channel.

  The waveform memory 10 stores waveform data of three types of musical tone information, the details of which will be described later, and the musical tone generator 9 reads waveform data from the waveform memory 10 in response to a key operation. The read address is incremented at a speed corresponding to the key code KC. That is, the waveform data is read at a reading rate corresponding to the key code KC. The tone generator 9 generates a tone signal based on the waveform data read from the waveform memory 10.

  The tone signal is converted to an analog signal by the DA converter 12 and then input to the sound system 13. The sound system 13 is composed of an amplifier, a speaker, and the like, and causes the output signal of the DA converter 12 to sound externally as an output of the electronic piano.

  The main function of the electronic piano will be described. In an acoustic piano, when a damper pedal is turned on and a key is depressed, a loud string resonance sound (first resonance sound) is generated due to an impact sound when the key is depressed. Hereinafter, the waveform of this loud string resonance sound is referred to as “musical sound resonance sound waveform”. On the other hand, when the damper pedal is turned on after the key is pressed, the damper is separated from the string and the resonance occurs while the key is already pressed. Therefore, the string resonance sound (second resonance sound) at this time is composed of a string resonance sound waveform (hereinafter referred to as “harmonic resonance waveform”) having only a harmonic component that does not include the string resonance sound caused by the impact sound when the key is depressed.

  Therefore, in the present embodiment, two types of musical sound information for generating a resonance sound are set according to the characteristics of such an acoustic piano, and musical sound information of a direct sound generated by pressing a key (hereinafter referred to as “normal sound”). A musical tone is generated based on three types of musical tone information. Normal sound generation system that generates normal sound by inputting waveform data of normal sound, first resonance sound generation system that generates musical sound resonance sound by inputting musical sound resonance sound waveform data including aperiodic components, and normal sound And a second resonance sound generation system for generating a harmonic resonance sound by inputting harmonic resonance sound waveform data of only a harmonic component excluding a non-periodic component that is an impact sound when a key is depressed.

  Furthermore, in the present embodiment, it is possible to generate a harmonic resonance sound that moderately attenuates so as to simulate the effect of a half pedal.

  FIG. 1 is a block diagram showing the main functions of the electronic piano according to this embodiment. In FIG. 1, a normal sound waveform storage unit 15, a musical sound resonance waveform storage unit 16, and a harmonic resonance resonance waveform storage unit 17 are provided. These storage units 15 to 17 are provided in the waveform memory 10. The normal sound waveform storage unit 15 stores normal sound waveform data in advance corresponding to all keys provided on the keyboard 8. The musical tone resonance waveform storage unit 16 and the harmonic resonance waveform storage unit 17 store in advance musical tone resonance waveform data and harmonic resonance waveform data corresponding to each normal sound. When key-on is detected by the key switch 8a, the detection signal is input as a sound generation instruction to the normal sound waveform storage unit 15, the musical tone resonance waveform storage unit 16, and the harmonic resonance waveform storage unit 17, and each waveform data is read out. It is.

  As a function of the tone generator, that is, the sound source means, a normal sound generator 18 and a resonance sound generator 19 are provided. The normal sound waveform data read from the normal sound waveform storage unit 15 is input to the normal sound generation unit 18. On the other hand, the musical tone resonance waveform data read from the musical tone resonance waveform storage unit 16 and the harmonic resonance waveform data read from the harmonic resonance waveform storage unit 17 are changed according to the switching of the resonance tone switching unit 20. Is selectively input to the resonance generator 19.

  The normal sound waveform storage unit 15 and the normal sound generation unit 18 constitute a normal sound generation unit, and a musical sound resonance sound waveform storage unit 16, a harmonic resonance sound waveform storage unit 17, a resonance sound switching unit 20, and a resonance sound generation unit 19 The resonance sound generating means is configured by.

  The normal sound generator 18 adds a normal sound envelope to the normal sound waveform data to generate a normal sound signal, and the normal sound signal is input to an adder 21 which is a musical sound mixing unit. The resonance generator 19 adds an envelope of resonance to one of the tone resonance waveform data and harmonic resonance waveform data, and generates a resonance signal (musical resonance signal or harmonic resonance signal). The resonance signal is generated and input to the multiplier 22. The multiplication unit 22 functions as a gate that generates or stops the generation of resonance by changing the level of the resonance signal supplied to the addition unit 21. For example, when the resonance signal is multiplied by the maximum multiplication coefficient scheduled by the multiplier 22, the resonance signal is at the maximum level, and the gate is opened. When the gate is opened, the resonance signal is input to the adder 21 and mixed with the normal sound signal to become a musical sound signal, which is supplied to the DA converter 12.

  The following functions are provided to process the normal sound waveform data, the musical sound resonance sound waveform data, and the harmonic resonance sound waveform data in the above-described units.

  First, a resonance sound waveform selection determination unit 23 that switches resonance sound switching unit 20 to select resonance sound waveform data is provided. The resonance sound waveform selection determination unit 23 compares the pedal depression amount PV input from the pedal sensor 7a with the resonance sound selection determination threshold value RT, and the tone resonance resonance waveform data and the harmonic resonance sound wave according to a predetermined determination criterion. Select one of the shape data. The resonance sound selection threshold value RT can be varied depending on the tone color or pitch. For example, resonance threshold selection threshold values RT corresponding to timbres or pitches are stored in advance as a table in storage means such as ROM 3, and based on the timbre instructed before performance and the key number at the time of key depression. It is preferable that the resonance sound selection determination threshold value RT be read. For example, the threshold value RT for resonance selection selection may be lowered for high sounds.

  In addition, a muffling determination unit 24 is provided that determines the damping speed during muffling by comparing the pedal depression amount PV input from the pedal sensor 7a with the muffling determination threshold value OT. The decay rate determined by the muffling determination unit 24 is set in the tone generation control unit 25 which is an envelope control means, that is, an envelope generator. The musical sound generation control unit 25 supplies the normal sound and the resonance sound envelope information including the attenuation envelope determined according to the set attenuation rate to the normal sound generation unit 18 and the resonance sound generation unit 19, respectively, to control the envelope. . It is preferable that the decay rate, that is, the decay time can be set individually for the normal sound and the resonance sound.

  Further, a gate opening determination unit 26 is provided for determining whether or not to generate a resonance signal by comparing the pedal depression amount PV input from the pedal sensor 7a with a gate opening threshold GT. The determination result of the gate opening determination unit 26 is input to the level control unit 27, and the level control unit 27 inputs the multiplication coefficient to the multiplication unit 22 according to the determination of the gate opening determination unit 26. For example, the multiplication coefficient can be a value that changes from “0” to “1.0” corresponding to the depression amount of the pedal 7. When the multiplication coefficient is “1.0”, the resonance signal with the maximum amplitude is input to the adding unit 21 so that a resonance can be generated. When the multiplication coefficient is “0”, the resonance signal is added to the adding unit 21. Therefore, no resonance sound is generated.

  The generation timing of the resonance sound based on the above configuration will be described with reference to FIG. FIG. 3 is a diagram showing a state where a resonance sound is generated according to the pedal depression amount PV. In FIG. 3, threshold values OT, RT, and GT are set for the pedal depression amount PV. As shown in the drawing, these threshold values are set in a relationship of “OT> RT> GT”. When the stepping amount PV is less than the threshold value GT (PV <GT), the gate opening determination unit 26 causes the level control unit 27 to output the multiplication coefficient “0” and does not generate a resonance signal. That is, when the depression amount PV is less than the threshold value GT, the pedal 7 is not depressed.

  When the depression amount PV is equal to or greater than the threshold value GT, a resonance sound is output. However, when the depression amount PV is less than the silencing determination threshold value OT (GT ≦ PV <OT), the pedal is a half pedal. The half pedal is further divided into two according to the resonance sound selection threshold value RT. When the depression amount PV is greater than or equal to GT and less than the threshold value RT (GT ≦ PV <RT), it is the lower half pedal of the half pedals, and a harmonic resonance is generated. In the situation of the lower half pedal, both the normal sound and the resonance sound change within the range of “high” when the key is released according to the depression amount PV. That is, unlike the case where the pedal 7 is not depressed (attenuation time is substantially zero), the tone generation control unit 25 controls the envelope so that a slight attenuation sound is generated.

  When the depression amount PV is greater than or equal to the threshold value RT and less than the threshold value OT (RT ≦ PV <OT), it is a half pedal, but it is close to a full pedal (upper half pedal), and a musical sound resonance sound is generated. The In this upper half pedal, since the pedal 7 is depressed considerably and close to the full pedal, the decay time when releasing the key is longer than that of the lower half pedal (attenuation speed “medium”), and the resonance sound is also increased. As described above, the tone generation control unit 25 and the level control unit 27 perform control.

  When the amount of depression PV is greater than or equal to the threshold value OT (PV> OT), the pedal is fully pedaled (pedal-on state), and a small decay speed is set so that the normal sound and resonance sound will continue to sound long after the key is released. Is done.

  In addition, although it is desirable to divide a half pedal into a lower half pedal and an upper half pedal, dividing into two is not essential. The full pedal generates a musical sound resonance sound, and the half pedal generates a harmonic resonance sound.

  Further, the level control unit 27 changes the multiplication coefficient from “0” to the scheduled value “1.0” over the first scheduled time when the pedal 7 is depressed (pedal-on operation), while the pedal 7 When the pedal is no longer depressed (pedal off operation), the multiplication coefficient is changed from the scheduled value “1.0” to “0” over a second scheduled time different from the first scheduled time. May be. The scheduled value “1.0” in the level control unit 27 can be varied according to the tone color or pitch. For example, scheduled values of levels (multiplication coefficients) corresponding to timbres or pitches are stored in advance as a table in storage means such as the ROM 3, and this value is determined based on the timbre instructed before performance and the key number at the time of key depression. It is preferable that the scheduled value can be read. For example, for high sounds, the planned value is lowered to reduce the maximum value of the resonance sound.

  Note that the musical sound resonance sound may be generated only when a specific key or a key in a specific key range is turned on. For example, the first resonance sound or the second resonance sound can be generated in the high sound range, and only the first resonance sound can be generated in the low sound range. That is, it is possible to generate a musical sound resonance sound only in a high range where the level of the direct sound is large.

  Next, the operation of the electronic piano will be described with reference to a flowchart. FIG. 4 is a flowchart showing the entire process of the electronic piano. In step S1, the CPU 1, RAM 4, sound source LSI (DSP), etc. are initialized. In step S2, panel event processing is performed in which the state of the switch or the like of the panel 5 is read and corresponding processing is performed. In step S3, a keyboard event process for generating a normal tone signal based on the output of the key switch 8a is executed. The keyboard event processing includes setting an envelope according to key touch (key press strength).

  In step S4, pedal event processing corresponding to the output of the pedal sensor 7a is performed. Note that the pedal event processing may include processing of pedals other than the pedal (damper pedal). In step S5, other processing is performed.

  FIG. 5 is a flowchart showing details of the keyboard event process (step S3). In step S30, the pedal depression amount PV is detected. That is, the output of the pedal sensor 7a is read. In step S31, the presence / absence of an on-event of the keyboard 8, that is, the presence / absence of key depression, is determined based on the presence / absence of an output from the key switch 8a. If the event is an on-event, the process proceeds to step S32, where the normal sound waveform data is read from the normal sound waveform storage unit 15 to the normal sound generating unit 18 according to the key information, and is input to the sound source LSI in the normal sound generating unit 18. A normal sound signal is generated based on the data to generate a normal sound.

  In step S33, as a function of the resonance sound waveform selection determination unit 23, the stepping amount PV is compared with the resonance sound selection determination threshold value RT to determine whether or not the stepping amount PV is equal to or greater than the threshold value RT. If the depression amount PV is equal to or greater than the threshold value RT, the process proceeds to step S34, where the resonance switching unit 20 is switched to the musical resonance waveform storage unit 16 side, and the musical resonance waveform data is read to the resonance generation unit 19. If the stepping amount PV is less than the threshold value RT, the process proceeds to step S35, the resonance switching unit 20 is switched to the harmonic resonance waveform storage unit 17 side, and the harmonic resonance waveform data is read to the resonance generation unit 19.

  If it is determined in step S31 that the event is not an on event, the process proceeds to step S36 to determine whether the event is an off event (key release). If it is not an off event, the keyboard event process is exited and the process returns to the overall process of FIG. When an off event is detected, the process proceeds from step S36 to step S37. In step S37, the depression amount PV is compared with the silencing determination threshold value OT as a function of the silencing determination unit 24. If the depression amount PV is equal to or greater than the threshold value OT, the pedal is full and the key depression state is substantially equal. Since they are the same and are not muted, the keyboard event process is exited and the process returns to the overall process of FIG. If the stepping amount PV is less than the threshold value OT, the process proceeds to step S38, and the tone generation control unit 25 attenuates and silences the normal sound according to the stepping amount PV. In step S39, the musical sound generation control unit 25 determines whether the upper half pedal or the lower half pedal is in accordance with the depression amount PV, and attenuates and cancels the resonance sound at a decay speed corresponding to the upper half pedal.

  FIG. 6 is a flowchart showing details of the pedal event process (step S4). In step S40, it is determined whether or not the pedal 7 is turned on, that is, whether or not the output of the pedal sensor 7a has changed from zero. If the pedal 7 is operated, it will progress to step S41 and will detect the depression amount PV. In step S42, as a function of the muffling determination unit 24, the depression amount PV is compared with the muffling determination threshold value OT to determine whether or not the depression amount PV is equal to or greater than the threshold value OT. If the depression amount PV is greater than or equal to the threshold value OT, that is, if it is a full pedal, the process proceeds to step S43, and the depression amount PV is determined to be gate open by the function of the gate opening determination unit 26 in order to control the output level of the resonance sound by the level control unit 27 It is judged whether it is more than threshold value GT for use.

  If the depression amount PV is equal to or greater than the threshold value GT, the process proceeds to step S44, and the resonance sound level is increased to the maximum value by the functions of the level control unit 27 and the multiplication unit 22. If the depression amount PV is less than the threshold value GT, the process proceeds to step S45, and the resonance level is reduced to zero by the functions of the level control unit 27 and the multiplication unit 22 to mute the resonance. When step S42 is affirmative, that is, when the pedal is a full pedal, the threshold value is in a relationship of OT> GT, so step S45 is not reached, but in the case where step S42 is negative, step S43 is performed. May be negative, and in this case, the process of step S45 is executed.

  If step S42 is negative, that is, if the pedal depression amount PV is less than the muting determination threshold value OT, the process proceeds to a release phase in which the sound being produced is attenuated and muted. First, in step S46, the normal sound being sounded is attenuated and muffled according to the depression amount PV by the functions of the musical sound generation control unit 25 and the normal sound generation unit 18. In step S47, along with the attenuation of the normal sound, the function of the musical sound generation control unit 25 and the resonance generation unit 19 attenuates and cancels the resonance sound being generated according to the depression amount PV.

  If step S40 is negative, that is, if the pedal is off, the process proceeds to step S48, and it is determined whether or not any pedal other than the pedal 7 has been operated. If step S48 is positive, processing corresponding to the pedal is performed in step S49. Since the process of step S49 is not a main part of the present invention, the details are omitted. If step S48 is negative, the pedal event process is skipped and the process returns to the overall process of FIG.

  Next, an example of creating musical tone resonance waveform data and harmonic resonance waveform data will be described. FIG. 7 is a block diagram illustrating a configuration of a main part of the resonance generator. The resonance generating device includes n filter circuits that generate resonance frequencies corresponding to the frequencies of n harmonics constituting the musical sound of each pitch name for each pitch name. FIG. 7 shows portions corresponding to the pitch names A0 and B0. The resonance circuit 35 includes a filter FA0-1 that generates a resonance frequency corresponding to the fundamental tone of A0, and filters FA0-2 to FA0-n that generate resonance frequencies corresponding to n harmonics. Similarly, the resonance circuit 36 includes a filter FB0-1 that generates a resonance frequency corresponding to the fundamental tone of B0, and filters FB0-2 to FB0-n that generate resonance frequencies corresponding to n harmonics. Adders 37 and 38 synthesize the outputs of the resonance circuit 35 and the resonance circuit 36, respectively. Further, the adder 39 synthesizes outputs of resonance circuits (not shown) provided corresponding to all pitch names including the resonance circuits 35 and 36.

  It should be noted that the resonance sounds are preferably created corresponding to all the pitch names (that is, all the keys of the keyboard 8), but are not necessarily created corresponding to all the keys of the keyboard 8. For example, in an acoustic piano, the names of pitches that are braked by a damper pedal are 69 keys from A0 to F6. Since keys other than the 69 keys have little resonance effect, it is not necessary to create a resonance sound.

  Further, as described above, it is preferable that the generated non-periodic resonance sound waveform data is read in response to a sound generation instruction (key press) of a specific sound or a sound of a specific high range.

  In the configuration of FIG. 7, when creating harmonic resonance sound waveform data, the harmonic component extracted from the recorded normal sound is used as input data to the resonance generator. Further, when creating musical sound resonance sound waveform data, the recorded normal sound is used as input data for the resonance generator.

  For example, when a harmonic component of a normal tone is input, each filter of the resonance circuit 35 outputs basic tone and resonance musical tone information in response to the input harmonic component. However, not only the resonance circuit 35 responds to the waveform data of the normal sound of A0, but other pitch names having the same resonance frequency as the fundamental tone and each harmonic frequency of A0 or a resonance frequency slightly deviated from them. The response filter also outputs resonance tone information in response. For example, resonance musical tone information is also output from a filter having a filter characteristic of the second overtone of A3 (441 Hz) that approximates the fundamental tone of A4 (440 Hz). The resonance musical tone information output from all the responding filters is synthesized by the adder 39, and the waveform data of the overtone resonance is output.

  As each filter circuit of the resonance circuit, it is preferable to use an IIR filter, which is designed to have a characteristic in which an output sharply rises in response to each input frequency. That is, the impulse response of the filter simulates a vibration waveform of a musical sound and can be reproduced by a one-degree-of-freedom viscous damping system model. For a one-degree-of-freedom viscous damping system model, the mass coefficient, damping natural frequency, and damping factor are model parameters. Based on this, the viscosity coefficient and stiffness coefficient that are the coefficients of the equation of motion of the one-degree-of-freedom viscous damping system model are calculated. Ask. Further, the equation of motion is Laplace transformed to obtain a transfer function expression of s expression. Then, the viscosity coefficient, the stiffness coefficient, and the mass are substituted into this transfer function equation, and bilinear transformation is performed to obtain a filter coefficient in z expression.

  The mass is an arbitrary value, the damped natural frequency is the frequency of the harmonic to be simulated, and the attenuation factor is a filter coefficient as an index when the attenuation of the harmonic is approximated by an exponential function.

  One filter is designed to simulate the time variation of the musical sound. However, if the time variation of the resonance frequency and amplitude is sufficiently simulated, the circuit scale becomes too large, so that it can be roughly simulated.

  Regarding the simulation of the vibration waveform by the one-degree-of-freedom viscous damping system model, a well-known method described in detail in Japanese Patent Application Laid-Open No. 2006-47451 can be applied, and thus detailed description thereof is omitted. Note that the musical sound resonance sound waveform data and the overtone resonance sound waveform data are not limited to being simulated by the one-degree-of-freedom viscous damping system model.

  In each of the above embodiments, an electronic piano is described as an example of an electronic musical instrument to which the resonance sound generating device is applied. However, the present invention is not limited to the electronic piano, and the present invention can be applied to other musical instruments. It is possible to take the same configuration within the scope of the invention.

It is a block diagram which shows the principal part function of the resonance generator which concerns on 1st Embodiment of this invention. It is a block diagram which shows the hardware component part of the resonance generator which concerns on embodiment of this invention. It is a figure which shows the pedal depression amount and the output condition of a resonance sound. It is a flowchart which shows the main process of a resonance generator. It is a flowchart which shows a keyboard event process. It is a flowchart which shows a pedal event process. It is a block diagram which shows the principal part structure of a resonant sound generation part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... CPU, 7 ... Damper pedal, 7a ... Pedal sensor, 8 ... Keyboard, 8a ... Keith switch, 10 ... Waveform memory, 15 ... Normal sound waveform memory | storage part, 16 ... Musical sound resonance sound wave memory | storage part, 17 ... Overtone resonance sound wave Shape storage unit, 18 ... normal sound generation unit, 19 ... resonance sound generation unit, 20 ... resonance sound switching unit, 22 ... multiplication unit (gate), 23 ... resonance sound waveform determination unit, 24 ... mute determination unit, 26 ... gate Judgment part

Claims (13)

A normal sound generating means for generating a normal sound in response to a pronunciation instruction;
Resonance sound generating means capable of selectively generating the first resonance sound and the second resonance sound of the normal sound in response to the sound generation instruction;
Resonance sound selection determination means for selecting one of the first resonance sound and the second resonance sound depending on whether or not the operation amount of the damper operator is equal to or greater than a resonance sound selection determination threshold;
Level control means for controlling the level of the resonance generated by the resonance generation means according to the operation of the damper operator;
Envelope control means for determining envelope control information for the normal sound generating means and the resonance sound generating means in response to an operation of a damper operator;
A resonance sound generating apparatus comprising: a tone mixing means for adding the normal sound and the resonance sound whose level is controlled by the level control means.   2. The resonance generating apparatus according to claim 1, wherein the resonance sound selection determination threshold is set in advance corresponding to a tone color or a pitch. The level control means comprises:
When the damper operation element is turned on, means for changing the resonance level from zero to a predetermined value in a first predetermined time;
Means for changing the level of the resonance sound from the first scheduled value to zero at a second scheduled time different from the first scheduled time when the damper operation element is turned off. The resonance generating apparatus according to claim 1 or 2, wherein   3. The level control unit according to claim 1, wherein the level control means is configured to change the level of the resonance sound from a predetermined value to zero corresponding to an operation amount of the damper operation element. Resonant sound generator.   5. The resonant sound generator according to claim 3, wherein a predetermined value of level change in the level control means is set in advance corresponding to a tone color or pitch.   The envelope control means is configured to individually control the decay time of the normal sound and the resonance sound during sound generation corresponding to the operation amount of the damper operator when the sound generation stop instruction is input. The resonance generator according to any one of claims 1 to 5.   The resonance generation means includes a waveform memory in which waveform data is stored, and sound source means for generating the first resonance sound or the second resonance sound based on the waveform data read from the waveform memory. The resonance generator according to any one of claims 1 to 6, wherein:   The waveform memory stores waveform data of the first resonance generated from the normal sound and waveform data of the second resonance generated from the harmonic overtone component of the normal sound. The resonance generator according to claim 7.   9. The apparatus according to claim 1, wherein the first resonance sound or the second resonance sound is generated when the sound generation instruction is a sound generation instruction in a predetermined pitch or pitch range. The resonance generating apparatus as described in any one.   Two resonance sound selection determination thresholds are provided, and when the operation amount of the damper operation element is equal to or higher than the resonance sound selection determination threshold value, the first resonance sound is selected and the damper operation element is selected. The first resonance sound decay time is set to be slower when the operation amount is higher or lower than the threshold value for resonance sound selection determination and higher than the threshold value for determination of high resonance sound selection. The resonance generator according to claim 1.   A gate opening determination threshold value is set below the resonance sound selection determination threshold value, and is selected by the resonance sound selection determination means when the operation amount of the damper operator is equal to or greater than the gate opening determination threshold value. 2. The resonance generating apparatus according to claim 1, wherein generation of the generated first resonance and second resonance is permitted. The waveform data of the first resonance and the waveform data of the second resonance are:
Waveform data obtained by inputting musical sounds to a circuit group in which a plurality of resonance circuits corresponding to harmonics of possible musical sounds are connected in parallel.
The resonance generator according to any one of claims 1 to 11, which is stored in advance in a waveform memory of the resonance generator. The resonance circuit has a digital filter, and the impulse response is a one-degree-of-freedom viscous damping system model simulating harmonic vibration waveforms.
Filter coefficients used in the digital filter are
Given the mass, damping natural frequency, and damping rate as model parameters for determining the behavior of the one-degree-of-freedom viscous damping system model, find the viscosity coefficient and stiffness coefficient that are the coefficients of the equation of motion of the model,
The Laplacian transformation of the equation of motion of the model is obtained to obtain a transfer function expression of s expression, and the obtained viscosity coefficient, stiffness coefficient and mass are substituted into this, bilinear transformation is performed to obtain a filter coefficient of z expression,
The mass is an arbitrary value, the damped natural frequency is the frequency of the harmonic to be simulated, and the damping rate is determined by obtaining the value as an index when the attenuation of the harmonic is approximated by an exponential function. The resonance generator according to claim 12, wherein:

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